The vaults as well as the remains of the walls in the cellar and the curtain wall at the lower terrace remind us of the castle complex of the counts of Orlamuende from the 13th century which the counts of Schwarzburg acquired in 1334. The curtain wall was part of a wall that enclosed the eastern defensive court. There is no evidence regarding the use or the design of this early complex that has been preserved.
In 1571, count Albrecht VII of Schwarzburg chose the castle as his permanent domicile and made Rudolstadt his residential town. He let the existing complex extend and rebuilt. Georg Robin from Mainz, one of the leading architects of his time, planned the construction works. On 25th March 1573 a fire destroyed parts of the wing containing the living rooms. As a consequence Albrecht VII used the former building to erect a palace complex with three wings. He initially assigned Georg Robin with the planning and later on Christoph Junghans from Arnstadt. After that the master builder Nikol Schleizer was responsible for the whole building process. Especially the southern wing had to be re-erected in 1573. This is documented by the inventory registers of the early 17th century which explicitly mention the rooms of the old castle and those of the new building facing the town. In 1576, the chapel of the palace, located at the northern wing, was consecrated.
The outwardly plain renaissance castle with its three floors was structured by strong cornices. Like other medium-sized castles in Middle Germany the roof of the building was adorned with lucarnes on the roof ornamented with volutes and several chimneys.
The linear order of the rooms of the southern wing illuminated from two sides and a constant floor level demonstrate that the transition from a castle to a palace had already taken place. Recent building researches indicate a sophisticated décor that would have met the demands of the counts of Schwarzburg-Rudolstadt. For example as ceilings from the 18th century had been removed, profiled beams carrying heavy joist ceilings made of wood came to light. Elaborate colour versions documented for some rooms of the southern wing give evidence of the influence of the big art centres. During the whole 17th century the construction of the renaissance palace remained almost unchanged.
A fundamental change regarding the construction process did not take place until the ennoblement of the house of Schwarzburg-Rudolstadt in 1710 when the counts became princes. From there on building operations that arose from the growing need of representation were set in motion. Prince Ludwig Friedrich I put a portal in the style of a triumphal arch in front of the access pointing towards the city to visually emphasis the bestowed majesty. In relation with it, safety works on the southern wing were carried out and supervised by Matthaeus Daniel Poeppelmann, a building master from Dresden. At this time they worked on the furnishing and decoration of some rooms, too. One of the earliest halls of mirrors in Middle Germany that still exists today was established around 1700.
When in 1735 a fire destroyed the western and northern wing up to the first floor the reigning prince, Friedrich Anton, decided to rebuild the western wing. The sketches were delivered by Johann Christoph Knoeffel, master builder from Saxony. His plans as well as their execution after 1737 outline the cool Dresdian late Baroque that the master builder implemented on many of his buildings. The rooms of the main floor that were important for the court ceremony Knoeffel structured following the French model of the »apartement double«. As a result, room units accommodating the variety of courtly life replace rooms simply adjacent to each other. Prince Friedrich Anton as well as his son, Johann Friedrich, sovereign since 1744, influenced the design of the western wing in an extensive way. Both of them occupied themselves with scripts concerning the theory of architecture and knew the trend-setting castles in the Netherlands and France from their own experience.
It was difficult to carry out Knoeffel’s ambitious construction plans because of the strained financial situation of the court of Schwarzburg-Rudolstadt. Therefore the princely government was forced to found a building commission in 1741. The head of the commission was the hereditary prince Johann Friedrich, who, after he had returned from his educational journey in France, took the building process into his hands. Making use of his good relations to the Weimar court he succeeded in gaining the master builder Gottfried Heinrich Krohne to work on the castle in Rudolstadt. This decision was justified with the reproach that Knoeffel, due to his responsibilities in Dresden, was no longer able to supervise the construction works in Rudolstadt with the necessary diligence. Thus Krohne was appointed »princely building director« in May 1743. This replacement, not lastly induced by Johann Friedrich, also entailed a change regarding the decoration of the rooms. As planned by his predecessor, Krohne maintained the arrangement of two apartments flanking the festive room but he changed the cool and classic interior decoration drafted by Krohne and introduced the delicacy and playfulness of the Rococo design.
When Prince Ludwig Guenther II ascended the throne in 1767 only minor changes on the main floor of the western wing were made. Later on, the main staircase as well as some rooms of the western and southern wing were decorated in the style of Classicism. Among others the master builders Ferdinand and Wilhelm Adam Thierry delivered numerous sketches for it. With the extension of the southern wing towards the east the building process of the palcae came to a preliminary stop during the first decade of the 19th century. The works at the Heidecksburg Palace made the court of Rudolstadt one of the centres of art in Thuringia.